Steve Baker (steve++at++mred.bgm.link.com)
Wed, 6 Nov 96 07:30:33 -0500
I think rou are running into a rather fundamental problem. If you have
80 degrees of the world on your CRT, then there is a certain amount of
'distortion' that is inevitable if your eye is not positioned such
the display occupies 80 degrees of your visual field. If you position your
eye correctly then the distortion will go away. Alternatively, you
should measure where the eye typically is with respect to the screen
and adjust your simulated FOV to match.
If you are using a conventional CRT such as the ones SGI supplied with
your machine - then you need to place your nose about 6" from the screen
to get an 80 degree FOV - it's hard to focus on the screen if you do that!
If you have a *much* larger screen (eg a projector or a video wall) then
larger fields of view work quite well.
Your trick of splitting the field of view into multiple channels only
has the effect of concentrating the distortion due to incorrect eye
position at the boundaries of the channels. The distortion is still
there - you just moved it around a bit! If you were to increase the number
channels, you would get more channel boundaries with less discontinuity
at each boundary. In the limit, if every pixel had it's own channel, you'd
get rid of the discontinuities - but you'd have a different fish-eye effect
which would require a curved display to eliminate.
Steve Baker 817-619-1361 (Vox-Lab)
Hughes Training Inc. 817-619-8776 (Vox-Office/Vox-Mail)
2200 Arlington Downs Road 817-619-4028 (Fax)
Arlington, Texas. TX 76005-6171 Steve++at++MrEd.bgm.link.com (eMail)
http://www.hti.com (external) http://MrEd.bgm.link.com/staff/steve (intranet)
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